Dscan

dscan is a unix like command-line tool written in TypeScript that helps you track dependencies and dependants in JavaScript projects

Repository

Quickstart

dscan allows you to quickly identify which files in your project are importing or being imported by specific packages. Here’s a simple example to get started.

Example: Find files that import a given package

$ dscan --json --root src graph/DependencyGraph.ts

Output

{
  "file": "/home/user/Projects/dscan/src/graph/DependencyGraph.ts",
  "dependencies": [
    "/home/user/Projects/dscan/src/graph/graphNode.ts"
  ],
  "dependants": [
    "/home/user/Projects/dscan/src/scanner/fileScanner.ts",
    "/home/user/Projects/dscan/src/formatter/outputter.ts",
    "/home/user/Projects/dscan/src/cli/cli.ts",
    "/home/user/Projects/dscan/src/index.ts"
  ]
}

This output shows the files that are imported by DependencyGraph.ts as well as the files that import it.

Example: Find files that import DependencyGraph.ts

To get a list of files that import DependencyGraph.ts, use the --reverse flag:

$ dscan --reverse --root src graph/DependencyGraph.ts

Output

/home/user/Projects/dscan/src/scanner/fileScanner.ts
/home/user/Projects/dscan/src/formatter/outputter.ts
/home/user/Projects/dscan/src/cli/cli.ts
/home/user/Projects/dscan/src/index.ts

Example: Get files imported by DependencyGraph.ts

To find the files that DependencyGraph.ts imports, simply run:

npx dscan --root src graph/DependencyGraph.ts

Output

/home/user/Projects/dscan/src/graph/graphNode.ts

Example: Using a custom tsconfig file

If your project uses a custom tsconfig file (e.g., tsconfig.app.json), you can specify it with the --tsconfig option:

$ dscan --tsconfig tsconfig.app.json --reverse --root src graph/DependencyGraph.ts

Output

/home/user/Projects/dscan/src/scanner/fileScanner.ts
/home/user/Projects/dscan/src/formatter/outputter.ts
/home/user/Projects/dscan/src/cli/cli.ts
/home/user/Projects/dscan/src/index.ts

Handling Missing tsconfig Files

If the tsconfig file specified does not exist or cannot be found, you will see a warning message like this:

$ dscan --tsconfig tsconfig.app.json --reverse --root src graph/DependencyGraph.ts

Warning output

[FileScanner] Warning: tsconfig file tsconfig.app.json not found at or above /home/user/Projects/dscan/src. Aliases will not be resolved.
/home/user/Projects/dscan/src/index.ts

Limitations

• Aliased imports through package.json (Import Maps): dscan currently does not support resolving module imports that are aliased through the imports field in package.json